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paddle/fluid/framework/details/ssa_graph.h

@@ -25,6 +25,7 @@ namespace details {
 
 struct SSAGraph {
   std::vector<std::unordered_map<std::string, std::map<int, VarHandle>>> vars_;
+  // aux variables to represent dependency. Useful to resolve data hazard.
   std::unordered_set<std::unique_ptr<VarHandleBase>> dep_vars_;
   std::vector<std::unique_ptr<OpHandleBase>> ops_;
 };

paddle/fluid/framework/details/threaded_ssa_graph_executor.cc

@@ -15,7 +15,6 @@
 #include "paddle/fluid/framework/details/threaded_ssa_graph_executor.h"
 
 #include "paddle/fluid/framework/details/fetch_op_handle.h"
-#include "paddle/fluid/framework/scope.h"
 
 namespace paddle {
 namespace framework {